A program that is CPU bound will benefit from compiler optimisations. Compiler optimisation wont make any noticable improvment on largely IO bound applications.
I was deliberatly speaking generally because it is a grey area, there are very few practical programs that are completely CPU bound or completely IO bound, compression certianly uses the CPU a lot, which is why i used it as an example, and it was about 15 seconds faster. I am not going to individually check every debian package just to give you "evidence" and some sort of blanket statment covering all released packages at a particualr instant in time. You comments on compiler bugs are irrelevent, it is not debians role to try and predict future compiler bugs, just to work around previous ones. Other than exposing bugs (which is a good thing) compiler optimisations do no harm. Glenn